The invention is concerned with such a separator of the kind comprising a matrix container means; matrix means within the matrix container means, magnetic means located in proximity to the matrix container means to establish zones of high and low magnetic intensity within the matrix container means; feed means for supplying a slurry to the matrix container means; washing means for washing material entrapped in the matrix means; launder means to receive matter discharged from the matrix container means, the launder means being arranged to receive respectively matter passing through the matrix container means at at least the high magnetic intensity and the low magnetic intensity zones; and moving means for causing relative movement between the container means and magnetic means. Such a separator is hereinafter referred to as a separator of the kind set forth.
Many known separators of the kind set forth are described in a paper entitled "Wet Magnetic Separation of Weakly Magnetic Minerals" by Lawver and Hopstock published in Minerals Science and Engineering, Volume 6, No. 3 of July, 1974, pages 154 - 172. In such known separators, the collector means normally comprises an annular collector ring or carousel, which rotates about its axis. The magnetic means comprise two or more pole pairs, the poles of each pair being located on a radius of the carousel with one within the centre of the carousel and the other outside the carousel. The matrices which may be used may comprise groove plates, salient pole plates, iron spheres, "wedge wire" bars, wire netting, steel wool, expanded metal sheets, rods, needles, bolts, helices, screens and the like. The feed means is normally located near and ahead of the zones of high magnetic intensity. Wash means are provided to remove matter entrapped in the matrix, being normally located at the low magnetic intensity zone for the magnetic material as well as at the high intensity zones for the non-magnetic materials. Further wash and launder means may be provided between these zones for middlings.
Such known separators of the kind set forth suffer from a number of disadvantages. The carousel tends to be extremely heavy. The problems of machining and/or fabricating the carousel appear, for the time being at least, to have imposed a maximum size of the carousel and hence a maximum capacity of the separator. The geometry of the carousel imposes limitations on the poles.
Further should the matrix become clogged, the entire separator must be shut down for the cleaning of the matrix.